Efficient modes extraction and numerically exact matched sources for a homogeneous waveguide cross-section in a FDTD simulation

Using the orthogonality of modes, an efficient real-time modes extraction is available for the finite-difference time-domain (FDTD) simulation of a waveguide. This paper demonstrates that, even at one cell beyond the discontinuity, S-parameters still can be accurately extracted. Combined with numerically exact matched sources, the computational volume for S-parameter computation can be reduced to a minimum.<>